Method of producing coffee extract



June 22, 1937.

E. F. DUBOIS METHOD OF PRODUCING COFFEE EXTRACT Filed Feb. 6, 1935' XNIVENTOR Mm ATTORNEY I Patented June 22,, 1937 Eugene F. Dubois, Freehold, N. J.

Application February 6, 1935, Serial No. 5,176

1 Claim.

This invention relates to improvements in methods of producing cofiee extract, the principal object of the invention being to provide a method by means of which an extract of coffee of excellent quality may be produced without the use of heat, whereby the natural flavor and aroma of the coifee is preserved in the extract, a very small quantity of which will be 'suflicient to make a delicious cup of cofiee.

I have found that the object of the invention can be achieved by taking cofiee pulverized to a fair degree of fineness, for instance about as fine as is ordinarily used for making what is known as drip coiiee, and wetting it with cold water while thoroughly kneading it so that every particle is saturated, and then packing the mass into a vessel and covering it with a body of cold water sufiicient to provide a head such as to caus the extract to flow from the saidvessel after a predetermined period of time. Experience has shown that best results are obtained by mixing and kneading together coffee and water in the approximate proportions of one pound of coflfee to twelve ounces of water, and, after packing the mass in a vessel as hereinbefore stated, covering it .with approximately twenty-four ounces of cold water, that is to say, water at room temperature, and permitting it to stand for approximately six hours. The vessel should be provided at its bottom with a tap for drawing ofi the'cofiee extract under the pressure of the water head above the coffee mass. Provision should also be inade for the evacuation of any air trapped in the vessel belowthe coffee mass so that such air will not work its way up through the coffee and'the water in the vessel. I

In the drawing accompanying this speciflcation, Fig. 1 is a perspective view of a vessel suitable 'for carrying. out the method above described, a part of the wall of said vessel being broken away to show theinterior thereof;

Fig. 2 is a plan view of a perforated disk which may be used as a part of the apparatus; and

Fig. 3 is a plan view of a screen disk which may also form-an element of the apparatus.

.Referring to the drawing, ldesignates a vessel which is preferably of approximately cone shape and of any suitable material. As shown herein the vessel is provided at the center of its I 1 i friction, or by thread connection, or in any other suitable manner. The plug 2 is provided with two perforations, in one of which is secured a short pipe 3 having a petcock 4, and in the other is secured the end of a long tube 5 which is bent upward outside of the plug and passes up paral- 5 lel with the wall of the vessel to a point above the water level in the vessel so that no liquid in the vessel will flow from the upper end of said tube.

In the concave space formed at the bottom 10 of the vessel immediately above the plug 2 is disposed a wad 6 of cotton-or other suitable fibrous material, and a screen or strainer l of copper or other suitable. metal and of proper diameter may, if desired, be disposed within the vessel im- 15 mediately above said concave space. The screen preferably should be provided at its center with a hook 8 for convenience in removing the screen from the vessel.

The vessel is further provided with a perfo- 20 rated disk 9 the diameter of which should be such as to fit within the vesselat a point just above the packed mass of saturated coifee. This disk also should be provided with a hook ill for convenience in removing the disk, and the under 25 surface and periphery thereof should be covered with a sheet or sheets of soft filter paper as indicated at II, Fig. 1. shown) may be'provided for the vessel.

The apparatus above described'is used in the 30 following manner. With the petcock 4' shut off andthe cotton wad 6 and screen I in place, a mass of coflee'which has been thoroughly saturated and mixed with water iiithe approximate proportions hereinbefore stated, is packed in the 35 vessel, the screen 1 forming a bottom for sustaining the weight of thecoffee. While the cofiee mass is being thus packed, any air that was trapped in the bottom of the vessel finds its 0 way out through the tube 5, so that the coffee 4 settlesin a solid mass entirely free from air bubbles. The perforated disk 9, with its filter paper, is then placed in positionabove the coffee mass, and a quantity of cold water, preferably in the proportion of twenty-four ounces to the pound of coffee, is poured into the vessel. The principal function of the filter paper is to pre-- vent the coffee frombacking up through the perforations of the disk and around its edge. After the coffee has been allowed to set for about six hours, the petcock l is opened whereupon a coflee extract of superior quality will drain of! through the tube 3. I have found in practice that the best results are obtained by taking oil.

A suitable cover (not I no more than sixteen ounces of extract from one Having thus described my invention, what I claim is:

The method of producing coffee extract which consists in kneading a mass of pulverized coifee and water, packing said mass into a receptacle and simultaneously forcing out the air from below the said mass, covering said mass with a body of water and permitting it to stand for a predetermined time, and then drawing ofi the liquid from said mass.

EUGENE F. DUBOIS. 

